Thermodynamic analysis of two-phase fluids stored in stationary and slowly moving tanks

[Truncated abstract] The present work deals with heat and mass transfer study of stationary and slowly moving, partially filled containers. The focus is on an increase in the mass transfer of the system due to vibration. For the stationary tank, the aim is to propose an optimum condition for (i) maximum mass transfer and (ii) minimum entropy generation rate. The study commenced with analysis of mass transfer and entropy generation of a storage container (asymptotic limit) for two cases: (a) open and (b) closed top systems and proceeded to the mass transfer study of a slowly moving container. For the moving tank the aim is to determine the effect of vibration on the mass transfer. A thermodynamic analysis of the two-phase physics involving a liquid-vapor combination had been studied under the regime of conjugate heat and mass transfer phenomena. An experiment had been designed and performed to estimate the interfacial mass transfer characteristics of a liquid-vapor system by varying the liquid temperature. The experimental set-up consisted of an instrumented stationary tank partially filled with water and maintained at different temperatures. The evaporation of liquid from the interface and the gaseous condensation had been quantified by calculating the interfacial mass transfer rate for both covered and uncovered tanks. The dependence of interfacial mass transfer rate on the liquid-vapor interfacial temperature, fractional concentration of the evaporating liquid, the surface area of the liquid vapor interface and the fill level of the liquid had been established through the present experimental study. An estimation of the overall mass transfer rate from the interface due to a concentration gradient showed an analogy with the multiphase heat transfer that took place across the interface due to the temperature gradient.